EDTA-AM (ethylenediaminetetraacetic acid, acetoxymethyl ester) represents the membrane-permeable version of the metal chelator EDTA. By incubating live cells with EDTA-AM, they passively absorb this compound. After entering the cell, cytoplasmic esterases break down the AM esters, liberating the active chelating agent EDTA that sequesters metal ions internally. The presence of EDTA-AM in cells leads to the cessation of mitotic progression and the decondensation of chromosomes [1] [2].

EDTA-AM treatment of mitotic cells involves several steps: First, collect mitotic cells and seed them onto a 12-well culture plate containing poly-L-lysine-coated coverslips, using DMEM supplemented with 10% FBS. Dissolve EDTA-AM in 100 mM DMSO and add it to the medium containing 0.02% Pluronic F-127 to a final concentration of 20 μM, then incubate the cells at 37°C for 100 minutes. After incubation, count the number of mitotic and interphase cells. Fix the cells on coverslips, stain them with DAPI, and mount using p-phenylenediamine (PPDI) solution [20 mM HEPES: pH 7.4, 1 mM MgCl2, 100 mM KCl, 78% glycerol, 1 mg/mL PPDI].